Home Forums Hunting & Shooting AR and Tactical Rifles FN 14.7" pinned/welded

I ordered this upper minus BCG from PSA. It came with the float tube, and a highly regarded FN barrel for $299 delivered. It's an A2 profile with mid-length gas system, 1/7 twist, cold hammer forged and double chrome-lined.

Should be fun. Just got her painted up, next stop the range.






Shane

Send the link. I'll order AR least one!!

Looks like they are out of stock right now.

http://palmettostatearmory.com/psa-...in-weld-without-bcg-or-ch-516446460.html

But they do have this one, with a different handguard and a bolt carrier group. On clearance too......

FN 14.7 inch

That'll work!

Good looking paint job!

I tried a different color scheme than I usually do. Used some Rustoleum colors from Walmart. I like the way it turned out.



Started with a sage green base coat,





Then accents with brown and tan, sprayed through some dry grass.

Took this rig out to zero yesterday.

Was getting odd results, 1 moa lateral spread, and 4 moa vertical spread.

When I got home I went over it in detail and found my trouble. I had installed a YHM M-Lok front swivel in the bottom of the float tube. I didn't pay close attention and had inadvertently ran the M-Lok hard against the bottom of the gas block, pushing the top of the gas block into the top of the float tube.

Not a lot of clearance on these low profile tubes. I relocated the front swivel back a notch, and got off the gas block. Everything is floating again.

Will get back out and re-zero soon, and get some chrono numbers.

What kind of loads are you looking to shoot?

I've got three loads on hand.

Yesterday was 77gr Nosler over 24.0 gr W748

Also have 53gr VMax over 24 gr XTerminator, and some milsurp Green Tip.

MM - if that Vmax load doesn't shoot as well as you'd like, try bumping up the powder charge more. I've used a bunch of XTerminator for 50-55gr bullets and almost always found that it shot best and was most consistent at or near max; ~2-2.5 gr higher than your 24gr charge. Ambient temps here are a little lower than you might have though so take that into account; 90 F is a pretty warm day for us.

WOW, that's a smoking deal; well done!!

Thanks. I know my load is modest. I loaded up a bunch for prairie dog shooting.

Got some velocity data today on a few loads.

I used a Magnetospeed for velocity data. 5-shot averages.

Accuracy data was 5-shots without the chrono attached.



- M855 'green tip' (PMC) - 2860 fps, 2 moa accuracy

- 53gr VMax/24gr XTerm - 2870 fps, 1.5 moa accuracy

- 77gr Nosler/24gr W748 - 2605 fps, 4 moa accuracy


I can see where the 53 VMax wants more powder, should be up around 3000 fps or so I believe.

Shane,

How do you like the Magnetospeed?

I like the Magnetospeed a lot. Small to pack, easy to set up, not light dependent. No lining up tripods. I have seen a rail adaptor out there for mounting it to semiauto pistol accessory rails.

The only con I can think of is it may shift your POI on a rifle.

Thanks

I have the magnetospeed and I love it. I sold my prochrono and never looked back. I always get good data, in any condition. Very useful for my high end airguns that I usually shoot indoors.

MM, to follow up on my previous comment, from a 16" AR I loaded up to 3000 fps with 55gr SP bullets and XTerminator, and up to 3180 with 50gr Vmax, with best accuracy at those top loads. I don't have a velocity for the 53 gr but one could make some educated guesses.

The 77gr Nosler load sounds disappointing. I had difficulty getting that one to shoot well too until I tried Benchmark; 23.5gr shot well with an S&B SR primer. Velocity should be ~2650 fps in your rifle. 8208 XBR seems to give pretty much the same results for the same powder charges so either one will work if you have them. ( I have been suspecting they may be the same powder with just lot to lot variations between them).

The Nosler 77 gr has been lackluster in other AR's, as well as the Ruger American Predator boltgun.

The 75gr Hornady BTHP shoots well in the other rifles, I need to load up a few to try in this one.

I settled on the 75gr Hornady BTHP as well. Loaded to 2.255" over 23.5gr of Benchmark and an S&B or Win SR primer prints small (.5-.7 moa) groups from my 16" 1:8 223 Wylde barrel at 2680 fps and has been good in everything else as well.

Grafs had good prices on 250 count bulk packs of them last summer, don't know if they still do but I need to stock up again. I still want to try the 73gr ELD though before buying a bunch more of the 75gr HP.

Some of my experiments with the 77gr Nosler with other powders resulted in 5-6" patterns at 100. And no, those weren't 5 or 10 shot groups, when they're that bad I quit at 3.

Sounds like that 77 Nosler is just fickle.



This pic is a different rifle. It's a 1/9 twist, and is about as good as I've ever got with the 77. 100 yard target.

The Sierra Match Kings have always shot better than the Noslers or the new tipped match kings. TAC or even better, Lever is worth a look.

Every time I see one of your painted guns, I want to break out the Krylon on mine. Looks good.

I like the look and smell of a freshly painted rifle.......it's like the new car smell.......smile

Shane,

Pardon my ignorance but what does 14.7" pinned/welded mean?

You inspired me further. Off to grab another beer and some Krylon... grin.




Dave

It just means the barrel is 14.7" from boltface to end of rifled barrel. The muzzle device is pinned and welded in place, bringing fixed length to meet the 16" minimum requirement.

10-4.

This rig is running fine with my handloads. But I believe it is a little over-gassed with the PMC XTAC 62gr.

The PMC load has the extractor jumping the rim, and leaving the case laying in the receiver, causing jams with the next round up. On a last round, it will lock the bolt back, but leave the spent case laying on top of the magazine. There is a heavy extractor mark on the spent case inside the rim.

Looks like I need an H2 buffer? I'm using the standard 3 oz carbine buffer right now.

I'd drop an H2 in that bitch yesterday.



Dave

I'm going to get an H2 on the way.

For now I slapped an A2 rifle buttstock and buffer assembly on it. That's a 5.1 oz. buffer.

The PSA FN barrels are gassed to run worst case- weak 223 with an H2 buffer.

You'll want an H2 (H3 might be worth a try), and ensure you have the SOCOM bolt upgrade kit for the extractor to use 5.56mm pressure Ammo.

Good info, thanks!

I've never even heard of that schit.




Dave

Better yet, just put on an adjustable gas block.

I just went through this with a new build that had a very large gas port in the barrel (had a .093" instead of a more normal .078-.080"). But the FN barrel shouldn't be that badly overgassed on the port size.

I'll be somewhat surprised if an H2 or even an H3 will be enough based on where you are at, but I assume you're starting with a carbine buffer, so maybe so.............PSA uses some really cheap ass springs too so you might want to put a slightly enhanced buffer spring in as well. Sprinco Blue is a slightly heavier than standard spring.

In my case, the H3 plus a heavier spring still wasn't enough..........ejection was at 1 o'clock with 5.56 & the lighter stuff barely got ejected & really didn't move going from an H1 to an H3.

And don't underestimate the value Formy's comment on the extractor spring upgrade either. You can get a Colt version here for a reasonable cost.

Colt Parts

As for the Nosler 77 grainer's, they don't do as well for me either as other bullets do, but they are good enough for most purposes but when I use up the current supply, I won't buy any more,

Here are some pics from load testing a while back. Powders & loads are shown if they are of any benefit to you.

This barrel has a .078" port on a .750" journal. Mid-length. (I pulled it apart and checked).

Lower is not PSA, but mix/match stuff I already had, from DPMS and AR-Stoner.

The buffer change & maybe the extractor upgrade too, should likely work then.

Good Luck............post up if that solves the issue for you; always good to get more data points on problem resolution.

MM

Similar- https://www.bravocompanyusa.com/BCM-Extractor-Spring-Uprade-Kit-p/bcm-exspring-1.htm

The rifle buffer system smoothed it right out. Makes me think the H2 or H3 should get the carbine system running right.



Here's a pic of the with the A2 stock/buffer system,





Comparison of extractor marks. The 5.1 oz rifle buffer was running real smooth. The 3.0 oz carbine system was jumping the rim and causing stoppages.

Learn something new every day.

Thanks.




Clark

A buffer likely will get you where you want to be based on your findings thus far. Albeit the cheapest alternative I too prefer and adjustable gas block. SLR is always a great choice but more and more I am liking both of my Suprelative Arms units.

Suprelative s unit can damper down gas the standard way by restricting gas into the block, they also have a hybrid mode. In these settings full gas enters the gas block yet gas to the gas tube is restricted with the excess exiting the block by way of an exhaust port in the front of the gas block.

This is especially nice for suppressor use

Shane,

anything special about 14.7" ? Or just a good price on FN barrel?

Sycamore

I just thought it was a good deal for an FN barreled upper. And I always kind of had an itch for the shorter length, but didn't really want to go through the SBR nut roll. So 14.7 is about as short as practical in that regard.

How much louder than a 16" or 18"? Can you tell a noticeable difference?

On any given day I have guys with 10.5", 11", 14.5," 16", and 18" M4's. You can't really notice a differamce between 14.5 and 16 or 18" barrels. Having said that, they're all permanently damaging with but a single unprotected shot, so one being "quieter" doesn't really matter. There is a noticeable difference in blast between the 10.5 and 11" guns and the 14.5" and longer, but again they're ALL permanently damaging with a single round being fired.

You can say that again.




Dave

"What was that?"


So, no real differences in muzzle blast either once you reach 14.5 or so?

In my experience a 16" barrel with no muzzle device is a helluva lot louder than this 14.7 with the A2 birdcage.

I don't find this obnoxious at all with the A2 device up front.

I use the spongy type of earplugs.

I think 14-18 is about the same.

Below 14 things get worse.

Above 18 things get better.

To me.




Dave

That's good to know. A shorter truck gun would be fun and useful.

Tagging this one for suppressor use. Thanks, Mallard.

I don't know if you're being literal or using that as a generic term, but IME an AR makes a less than ideal truck gun. It tosses brass all over and into the heater vents. Not to mention the pistol grip and mag well refuse to ride between the seat and center console comfortably.




Travis

We can't actually shoot "in or on" a motor vehicle here, so it necessitates getting out anyway.

My truck doesn't have a center console either, so I just throw a rifle muzzle down on the floorboards or chuck it on the floor behind the seat (usually the latter).

The tractor cab in the summer is really where it would get more everyday use.

Okay, I believe I've got this rig dialed in. Finished it up with a Primary Arms 5X prism sight with an 800 yard reticle, and a Magpul MOE rifle buttstock.

I like the way it looks and feels.





Rain is on the way, and I'll get some more trigger-time soon, without concern for starting a fire.

Nice looking, dialed in now, how well is the barrel shooting?

I have hearing aids now, and I shot a lot of 5.56 without hearing protection when I was a lot younger. I have hunted recently with 16 inch guns with the birdcage on the end, honestly for 1 shot it did not seem to bother, 1 shot = 1 deer, on the other hand I wore out a bunch of pigs one day and the reason I stopped shooting was not because there were no more pigs, nor because I out of cartridges. These days I keep a pair of cheap howard Leigh electronic ear pro on my cap, I know there are better models and I tried the pro ear's gold but am not impressed with the battery type, nor its performance, one ear has a buzzing sound for 4 times the money. I hope to be able to afford sordin's one day.

I am intrigued by the DD SLW light weight barrel with 14.5 pinned, its a lot lighter and I have had great experiences with their LW barrels. Another on the wish list!

The fire conditions have been so bad the last month I haven't shot it, or anything else lately. We have some rain on the way over the next four days or so. That should help douse some of the wildfire around here, and I'll get back out there and do some more shooting.

I think it will shoot well for a chrome-lined AR-15. By that I mean 1.5 moa or so with M855. I'll put together some handloads with Hornady 75gr BTHP and see how they do, probably a little better than the M855 I would imagine.

The last time I shot it I had just put the rifle recoil system back on it and that solved my extraction issues I'd been having with the carbine recoil system with 3.0 oz buffer.

With the cool weather and moisture I got this carbine out to test a few rounds, and zero the optic.

Pretty breezy today so I decided to reduce the wind effect by zeroing my 200 yard reticle index at 50 yards, knowing 50/200 line up well with the AR.

Considering 15-25 mph winds, I'm happy with the accuracy I saw. After zeroing, I ran the M855 on some rocks out to 670 yards. The reticle on the Primary Arms 5X works very well.

Some pics,









Some Glock 19 time,





Snow on the Elkhorn Mountains,

What optic do you have on the rifle? I don't know how PSA does it at the prices they sell for. The FN barrel does not shoot bad at all. Wish they made a 14.5 LW floated upper.

The optic is a Primary Arms 5X prism sight. I'm not that familiar, this is my first one. They are kind of a poor-man's ACOG. They seem pretty sturdy. The reticle is nice, etched glass with red and green illum.

http://www.primaryarms.com/primary-...-223-5-56-5-45x39-308-acss-reticle-pac5x

Looks good Shane man.




Dave

Primary Arms has made me a customer. I was a little skeptical of the quality of their optics before, given the price. Not any more. This 1-6x24 ACSS, another poor man's ACOG, is nice glass for $246 with $43 Amazon freebee $$'s. Illuminated BDC reticle for 7.62x39 or 300BO. 12 brightness settings. Very clear edge to edge. Picks up light very well in low light situations. If everything they make is like this, I'm sold.

http://www.primaryarms.com/primary-...k-7-62x39-reticle-pa1-6x24sfp-acss-300bo



Hoping to stretch this one's legs in Montanastan in a couple weeks.

I read a lot of reviews and watched a few youtube vids on Primary Arms stuff before I took the plunge. They seem to get good reviews.

Shall I make up the spare room?




Dave

Flave, thanks. But, I was groggy late last night and it should have read Wyomistan.

Greatly appreciate the offer, though.

Another range session. I'm really liking this carbine. Calm day, and M855 green tip holding decent accuracy at 100 yards, sub 2-inch.

Also some shots with the 308, and 208 Amax.

I ended up going back to the carbine stock. I really like this prism sight, but eye relief was a little too long on the rifle stock, and only got worse with heavier clothing.




I followed this excellent advice,



New extractor including new spring/plunger/o-ring, and an H3 buffer. Runs great now with an authoritative 'thu-thunk' as that H3 buffer drives the bolt home. Brass shows barely visible extractor claw marking.

I'm done.

Nice.




Travis

I'm liking the reticle on this sight. Seems to track right on with M855. I've had it out to 670 yards and right on the money.

The reticle is etched so it all shows black when illum is off.

I think I put something similar on my Ruger Scout.

Other than the weight I really like it. Well thought out.




Travis

Yeah mine isn't exactly a featherweight at 17 oz.

I was weighing it against a SWFA 1-4 Illum. That one is 14 oz, but when you add mounting hardware the weight difference is a wash.

Shane did you by chance weight the upper? I looked on their website and no weight listed. I had been trying to find a DD SLW upper (pencil barrel) but curious what this one weights if you know off hand.

I just put the upper on the scale,


With BCG/CH - 4lb 2oz.

Without BCG/CH - 3lb 6oz.

That includes a YHM M-LOK front sling point, and Krylon. Probably a couple ounces in that.

The whole carbine with optic, sling, 20 round mag with 18 rounds of M855 as shown in the last pic is 8lb 8oz.

Add the Harris 9-13 swivel/notched leg bipod, we're at 9lb 5oz.

Thank you for that, 4 pounts/2oz. I wonder how much a pencil barrel actually saves in weight? Then I cannot believe a DD barrel is any better than a double chromed FN barrel, both probably 2MOA or so best case with M855.

I pulled the stocks on my 6920 and 6720 that are otherwise equipped exactly the same, 6920 weighs 6.2 lbs, 6720 weighs 5.8 lbs.

6 ounces... I just have to wonder if the DD barrel is worth the additional $600 you would put into a DD upper, if you put a Colt BCG into the PSA I think your at about $500 but the PSA is out of stock for a while now.

Which barrel are you looking for?

For shooting ball ammo? No.

PSA has some good deals and the FN barrels seem to be pretty good from reviews but I have no experience with them. If they made a pencil barrel at 16" I would change that, I don't like 14.5" barrels simply because they are a PIA to change up not to mention the loss in velocity. If one didn't change things around like I'm prone to do then it would be ok.

Looking at DD's website, they list the following weights,

14.5" LW, stripped - 1.25 lbs
14.5" M4, stripped - 1.6 lbs


I think that works out to about 5 oz difference.

Not huge for sure. thanks I did not find that. For ball ammo I shoot more of that than anything else but every once in a while I will fire some reloads at live animals. My older DD LW 16.5 inch barrel I shot in the challenge with 55 grain vmax is 1.5 MOA for 10 IIRC.

I found the weight info on DD's barrels here,

https://danieldefense.com/cold-hammer-forged-barrels.html